1. Field of the Invention
This invention relates to a diesel engine crankcase lubricating composition which exhibits improved resistance to corrosion and oxidation. More particularly, this invention relates to a novel corrosion and oxidation resistant diesel engine crankcase lubricating composition comprising a major amount of a hydrocarbon lubricating oil and a minor amount of the reaction product of a dibasic acid anhydride reactant, a polyoxyalkylene diamine reactant, and a heterocyclic azole reactant. The instant invention is particularly useful as a lubricant in large diesel engines such as marine and railway diesel engines.
2. Information Disclosure Statement
U.S. Pat. No. 4,865,622 discloses an ORI-inhibited and deposit-resistant motor fuel composition comprising an additive composition which is the reaction product of a dibasic acid anhydride, a polyoxyalkylene diamine, and a heterocyclic azole.
Co-assigned U.S. Pat. No. 4,758,363 (Sung et al.) discloses an oxidation and corrosion-resistant diesel engine lubricant composition comprising a major amount of a hydrocarbon lubricating oil and a minor amount of the reaction product prepared by first reacting a hydroxybenzoic acid with a polyoxyalkylene polyol to produce an ester, and thereafter reacting the esterification product with an aldehyde or ketone and a substituted or unsubstituted heterocyclic azole to form the final reaction product.
Co-assigned U.S. Pat. No. 4,705,642 (Sung et al.) discloses a haze, oxidation, and corrosion-resistant diesel engine lubricant composition which comprises a major amount of a hydrocarbon lubricating oil and a minor amount of the reaction product of an anhydride compound, a hydrocarbon-substituted mono primary amine or ether amine, and a nitrogen-containing heterocyclic azole or polyalkylene polyamine compound.
Co-assigned U.S. Pat. No. 4,464,276 (Sung et al.) describes the preparation of novel polyoxyalkylene polyamine-triazole complexes and their use in diesel lubricant compositions as antioxidants and corrosion-inhibitors.
Co-assigned U.S. Pat. No. 4,285,823 (Sung et al.) discloses a diesel engine lubricant composition comprising a corrosion inhibitor which is the reaction product of an N-alkyl-1,3-propane diamine, formaldehyde, and a 5-aminotetrazole.